schemadiff: temporal range partition rotation analysis and operation

go/mysql/config/config.go

@@ -3,3 +3,4 @@ package config
 const DefaultSQLMode = "ONLY_FULL_GROUP_BY,STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_ENGINE_SUBSTITUTION"
 const DefaultMySQLVersion = "8.0.30"
 const LegacyMySQLVersion = "5.7.31"
+const Lts84MySQLVersion = "8.4.3"

go/mysql/datetime/interval.go

@@ -166,6 +166,54 @@ func (itv IntervalType) ToString() string {
 	}
 }
 
+// IntervalTypeFromString parses a string into an IntervalType. This is the inverse function of IntervalType.ToString().
+func IntervalTypeFromString(s string) IntervalType {
+	switch strings.ToLower(s) {
+	case "year":
+		return IntervalYear
+	case "quarter":
+		return IntervalQuarter
+	case "month":
+		return IntervalMonth
+	case "week":
+		return IntervalWeek
+	case "day":
+		return IntervalDay
+	case "hour":
+		return IntervalHour
+	case "minute":
+		return IntervalMinute
+	case "second":
+		return IntervalSecond
+	case "microsecond":
+		return IntervalMicrosecond
+	case "year_month":
+		return IntervalYearMonth
+	case "day_hour":
+		return IntervalDayHour
+	case "day_minute":
+		return IntervalDayMinute
+	case "day_second":
+		return IntervalDaySecond
+	case "hour_minute":
+		return IntervalHourMinute
+	case "hour_second":
+		return IntervalHourSecond
+	case "minute_second":
+		return IntervalMinuteSecond
+	case "day_microsecond":
+		return IntervalDayMicrosecond
+	case "hour_microsecond":
+		return IntervalHourMicrosecond
+	case "minute_microsecond":
+		return IntervalMinuteMicrosecond
+	case "second_microsecond":
+		return IntervalSecondMicrosecond
+	default:
+		return IntervalNone
+	}
+}
+
 func intervalSetYear(tp *Interval, val int) {
 	tp.year = val
 }

go/mysql/datetime/interval_test.go

@@ -17,9 +17,12 @@ limitations under the License.
 package datetime
 
 import (
+	"math"
+	"strings"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 
 	"vitess.io/vitess/go/mysql/decimal"
 )
@@ -367,3 +370,47 @@ func TestInRange(t *testing.T) {
 		assert.Equal(t, tc.wantInRange, got)
 	}
 }
+
+func TestIntervalTypeFromString(t *testing.T) {
+	intervals := []IntervalType{
+		IntervalMicrosecond,
+		IntervalSecond,
+		IntervalMinute,
+		IntervalHour,
+		IntervalDay,
+		IntervalWeek,
+		IntervalMonth,
+		IntervalQuarter,
+		IntervalYear,
+		IntervalSecondMicrosecond,
+		IntervalMinuteMicrosecond,
+		IntervalMinuteSecond,
+		IntervalHourMicrosecond,
+		IntervalHourSecond,
+		IntervalHourMinute,
+		IntervalDayMicrosecond,
+		IntervalDaySecond,
+		IntervalDayMinute,
+		IntervalDayHour,
+		IntervalYearMonth,
+	}
+	for _, interval := range intervals {
+		s := interval.ToString()
+		t.Run(s, func(t *testing.T) {
+			require.NotEmpty(t, s)
+			require.NotEqual(t, "[unknown IntervalType]", s)
+			parsed := IntervalTypeFromString(s)
+			assert.NotEqual(t, IntervalNone, parsed)
+			assert.Equal(t, interval, parsed)
+
+			parsed = IntervalTypeFromString(strings.ToUpper(s))
+			assert.NotEqual(t, IntervalNone, parsed)
+			assert.Equal(t, interval, parsed)
+		})
+	}
+	interval := IntervalType(math.MaxUint8)
+	s := interval.ToString()
+	assert.Equal(t, "[unknown IntervalType]", s)
+	parsed := IntervalTypeFromString(s)
+	assert.Equal(t, IntervalNone, parsed)
+}

go/vt/schemadiff/diff_test.go

@@ -587,9 +587,11 @@ func TestDiffSchemas(t *testing.T) {
 		diffs       []string
 		cdiffs      []string
 		expectError string
-		tableRename int
 		annotated   []string
+		// hints:
+		tableRename int
 		fkStrategy  int
+		rotation    int
 	}{
 		{
 			name: "identical tables",
@@ -922,6 +924,35 @@ func TestDiffSchemas(t *testing.T) {
 				"ALTER TABLE `t` RENAME INDEX `i_idx` TO `i_alternative`",
 			},
 		},
+		// Partitions
+		{
+			name:     "change partitioning range: statements, add",
+			from:     "create table t1 (id int primary key) partition by range (id) (partition p1 values less than (10), partition p2 values less than (20))",
+			to:       "create table t1 (id int primary key) partition by range (id) (partition p1 values less than (10), partition p2 values less than (20), partition p3 values less than (30))",
+			rotation: RangeRotationDistinctStatements,
+			diffs: []string{
+				"alter table t1 add partition (partition p3 values less than (30))",
+			},
+			cdiffs: []string{
+				"ALTER TABLE `t1` ADD PARTITION (PARTITION `p3` VALUES LESS THAN (30))",
+			},
+		},
+		{
+			name:     "change partitioning range: statements, multiple drops, distinct",
+			from:     "create table t1 (id int primary key) partition by range (id) (partition p1 values less than (10), partition p2 values less than (20), partition p3 values less than (30))",
+			to:       "create table t1 (id int primary key) partition by range (id) (partition p3 values less than (30))",
+			rotation: RangeRotationDistinctStatements,
+			diffs:    []string{"alter table t1 drop partition p1, p2"},
+			cdiffs:   []string{"ALTER TABLE `t1` DROP PARTITION `p1`, `p2`"},
+		},
+		{
+			name:     "change partitioning range: statements, multiple, assorted",
+			from:     "create table t1 (id int primary key) partition by range (id) (partition p1 values less than (10), partition p2 values less than (20), partition p3 values less than (30))",
+			to:       "create table t1 (id int primary key) partition by range (id) (partition p2 values less than (20), partition p3 values less than (30), partition p4 values less than (40))",
+			rotation: RangeRotationDistinctStatements,
+			diffs:    []string{"alter table t1 drop partition p1", "alter table t1 add partition (partition p4 values less than (40))"},
+			cdiffs:   []string{"ALTER TABLE `t1` DROP PARTITION `p1`", "ALTER TABLE `t1` ADD PARTITION (PARTITION `p4` VALUES LESS THAN (40))"},
+		},
 		// Views
 		{
 			name: "identical views",
@@ -1043,6 +1074,7 @@ func TestDiffSchemas(t *testing.T) {
 			hints := &DiffHints{
 				TableRenameStrategy:     ts.tableRename,
 				ForeignKeyCheckStrategy: ts.fkStrategy,
+				RangeRotationStrategy:   ts.rotation,
 			}
 			diff, err := DiffSchemasSQL(env, ts.from, ts.to, hints)
 			if ts.expectError != "" {

go/vt/schemadiff/env.go

@@ -17,6 +17,13 @@ func NewTestEnv() *Environment {
 	}
 }
 
+func New84TestEnv() *Environment {
+	return &Environment{
+		Environment: vtenv.New84TestEnv(),
+		DefaultColl: collations.MySQL8().DefaultConnectionCharset(),
+	}
+}
+
 func NewEnv(env *vtenv.Environment, defaultColl collations.ID) *Environment {
 	return &Environment{
 		Environment: env,

go/vt/schemadiff/errors.go

@@ -256,6 +256,16 @@ func (e *InvalidColumnInPartitionError) Error() string {
 		sqlescape.EscapeID(e.Column), sqlescape.EscapeID(e.Table))
 }
 
+type UnsupportedRangeColumnsTypeError struct {
+	Table  string
+	Column string
+	Type   string
+}
+
+func (e *UnsupportedRangeColumnsTypeError) Error() string {
+	return fmt.Sprintf("unsupported column type %s for column %s indicated by RANGE COLUMNS in table %s", e.Type, e.Column, e.Table)
+}
+
 type MissingPartitionColumnInUniqueKeyError struct {
 	Table     string
 	Column    string